Although a first-degree conviction normally would warrant a 10 to 20-year prison sentence, a Superior Court judge in 2013 downgraded the charge and sentenced Plank to just five years. Plank, however, has remained free as both she and prosecutors appealed the convictions and sentencing.

Prosecutors say the Martinsville section resident sold heroin to Christopher Coppola, 20, of Bridgewater, and Sara Malaker, of Springfield, in 2009. Malaker’s mother found the couple dead in her daughter’s bedroom the next day.

Investigators found text messages showing Plank and Malaker arranging to meet at a home in the Finderne section, but the appellate decision noted that “the jury heard from no one who saw defendant possess or distribute the drug.”

Plank’s appeal argued that she was denied her constitutional right to confront her accuser because the medical examiner who conducted the autopsies had been forced out of his job in Union County and prosecutors did not call him to testify citing concerns with the expense. Instead, the new medical examiner testified by relying on his predecessor’s notes.

The autopsy had concluded that Coppola had accidentally died from acute intoxication of heroin, Xanax, Clonazepam and cannabinoids, while Malaker accidentally died as a result of acute morphine intoxication with bronchial asthma.

During the trial, a forensic pathologist called by the defense testified that the position of Malaker's body indicated that she had succumbed to an asthma attack triggered by the panic and anxiety of seeing her boyfriend overdosing.

The appellate decision also found the medical examiner’s testimony “problematic” because he said medical examiners have a “routine practice” of citing drug use as a principal cause of death while attributing any underlying health conditions as a contributing cause.

“Although the evidence of heroin ingestion was overwhelming, we are not satisfied, beyond a reasonable doubt, that the violation of defendant’s confrontation rights was harmless,” the appellate decision says.

Plank remains guilty of third-degree drug dealing, for which she was sentenced to four years. Prosecutors could seek to take her to trial again on the first-degree charges.

A spokesman for the Union County Prosecutor’s Office said Wednesday that the office "will be weighing its options in this matter going forward.”